[Bug java/28938] [ecj] update build instructions to account for changes

["bonzini at gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #1 from bonzini at gnu dot org  2006-09-13 10:43 -------
A somewhat disconnected comment on the ecj-branch build process...

Are you planning to distribute ecj as a JAR file too?  If so, there should be
no changes to the documentation for building out of tarballs.

If you don't want to put the JAR in svn, To build from svn, a pre-existing GCJ
would be necessary that can build ecj.

The build process should go like this:

- the gcc directory builds the bytecode->native compiler
- if there is a JAR, the ecj directory looks for ../gcc/gcj and uses that one
to build the native compiler
- if not, the toplevel configury should pass the path to a GCJ somewhere and
the ecj directory will use it to build the JAR.  I think the JAR should be
built in the build directory, unless --enable-generated-files-in-srcdir.

more on the third bullet: find the GCJ in the toplevel, as we do for C++ (grep
for CXX= in the toplevel configure -- there is room for improvement but I don't
think it's important).  In the Makefile.tpl, add somewhere

  GCJ=@GCJ@

and pass it down to ecj via HOST_FLAGS_TO_PASS.

Later on, ecj could even be bootstrapped using POSTSTAGE1_FLAGS_TO_PASS to
point to the just build gcj and ecj.  (How does gcj find the ecj to use?  Might
this require spec hacking?)


-- 

bonzini at gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |bonzini at gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28938